perf(clients): sort projects and settled threads without re-parsing dates per comparison

apps/mobile/src/features/threads/threadListV2.ts

@@ -14,6 +14,7 @@ import {
   sortActiveThreadsByOrderKey,
   resolveSettledThreadTimestamp,
   sortPinnedThreadsByOrderKey,
+  sortSettledThreads,
 } from "@t3tools/client-runtime/state/thread-sort";
 import type { EnvironmentId, ProjectId } from "@t3tools/contracts";
 
@@ -606,11 +607,7 @@ export function buildThreadListV2Items(input: {
       : orderedSnoozed.filter(
           (thread) => `${thread.environmentId}:${thread.id}` === selectedThreadKey,
         );
-  const orderedSettled = [...settled].sort(
-    (left, right) =>
-      parseTimestampMs(resolveSettledThreadTimestamp(right) ?? "") -
-      parseTimestampMs(resolveSettledThreadTimestamp(left) ?? ""),
-  );
+  const orderedSettled = sortSettledThreads(settled);
   const settledLimit = input.settledLimit ?? Number.POSITIVE_INFINITY;
   const pagedSettled =
     orderedSettled.length > settledLimit ? orderedSettled.slice(0, settledLimit) : orderedSettled;

apps/web/src/components/Sidebar.logic.test.ts

@@ -31,7 +31,6 @@ import {
   shouldClearThreadSelectionOnMouseDown,
   shouldRecedeSidebarThread,
   sortLogicalProjectsForSidebar,
-  sortSettledThreadsForSidebar,
   resolveSidebarDropTarget,
   pinOrderKeyBetween,
   planPinnedReorder,
@@ -51,6 +50,7 @@ import {
   resolveSidebarDropVerb,
 } from "./Sidebar.logic";
 import { threadSearchMatchKey } from "@t3tools/client-runtime/state/thread-search";
+import { sortSettledThreads } from "@t3tools/client-runtime/state/thread-sort";
 import {
   EnvironmentId,
   OrchestrationLatestTurn,
@@ -1690,12 +1690,12 @@ describe("applySidebarThreadDrop", () => {
     };
     const existing = { ...newer, settledOverride: "settled" as const, settledAt: newer.createdAt };
     expect(preview).toEqual({ ...final, settledAt: now });
-    expect(sortSettledThreadsForSidebar([existing, preview]).map((row) => row.id)).toEqual([
+    expect(sortSettledThreads([existing, preview]).map((row) => row.id)).toEqual([
       "dragged",
       "newer",
     ]);
-    expect(sortSettledThreadsForSidebar([existing, preview]).map((row) => row.id)).toEqual(
-      sortSettledThreadsForSidebar([existing, final]).map((row) => row.id),
+    expect(sortSettledThreads([existing, preview]).map((row) => row.id)).toEqual(
+      sortSettledThreads([existing, final]).map((row) => row.id),
     );
   });
 
@@ -1710,7 +1710,7 @@ describe("applySidebarThreadDrop", () => {
     const final = { ...source, snoozedAt: null, snoozedUntil: null };
     const existing = { ...newer, settledOverride: "settled" as const, settledAt: newer.createdAt };
     expect(preview).toEqual(final);
-    expect(sortSettledThreadsForSidebar([existing, preview]).map((row) => row.id)).toEqual([
+    expect(sortSettledThreads([existing, preview]).map((row) => row.id)).toEqual([
       "newer",
       "dragged",
     ]);
@@ -1820,74 +1820,6 @@ describe("sortPinnedThreadsForSidebar", () => {
   });
 });
 
-describe("sortSettledThreadsForSidebar", () => {
-  const settled = (input: {
-    id: string;
-    settledAt?: string | null;
-    latestUserMessageAt?: string | null;
-    latestTurn?: OrchestrationLatestTurn | null;
-    updatedAt?: string;
-  }) => ({
-    id: input.id,
-    settledAt: input.settledAt ?? null,
-    latestUserMessageAt: input.latestUserMessageAt ?? null,
-    latestTurn: input.latestTurn ?? null,
-    updatedAt: input.updatedAt ?? "2026-03-09T09:00:00.000Z",
-  });
-
-  it("orders by settle time, most recently settled first", () => {
-    const sorted = sortSettledThreadsForSidebar([
-      settled({
-        id: "settled-first",
-        settledAt: "2026-03-09T10:00:00.000Z",
-        // Created/active later than the other thread: settle time must win.
-        latestUserMessageAt: "2026-03-09T09:59:00.000Z",
-      }),
-      settled({
-        id: "settled-last",
-        settledAt: "2026-03-09T12:00:00.000Z",
-        latestUserMessageAt: "2026-03-09T08:00:00.000Z",
-      }),
-    ]);
-
-    expect(sorted.map((thread) => thread.id)).toEqual(["settled-last", "settled-first"]);
-  });
-
-  it("falls back to last activity for auto-settled threads without a settledAt stamp", () => {
-    const sorted = sortSettledThreadsForSidebar([
-      settled({ id: "auto-old", latestUserMessageAt: "2026-03-09T08:00:00.000Z" }),
-      settled({ id: "explicit", settledAt: "2026-03-09T10:00:00.000Z" }),
-      settled({ id: "auto-recent", latestUserMessageAt: "2026-03-09T11:00:00.000Z" }),
-    ]);
-
-    expect(sorted.map((thread) => thread.id)).toEqual(["auto-recent", "explicit", "auto-old"]);
-  });
-
-  it("counts a turn completion as activity for auto-settled threads", () => {
-    // The message came in before the other thread's, but its turn finished
-    // after: completion time is the real "work ended" moment.
-    const sorted = sortSettledThreadsForSidebar([
-      settled({ id: "message-only", latestUserMessageAt: "2026-03-09T10:04:00.000Z" }),
-      settled({
-        id: "completed-later",
-        latestUserMessageAt: "2026-03-09T10:00:00.000Z",
-        latestTurn: makeLatestTurn({ completedAt: "2026-03-09T10:30:00.000Z" }),
-      }),
-    ]);
-
-    expect(sorted.map((thread) => thread.id)).toEqual(["completed-later", "message-only"]);
-  });
-
-  it("breaks timestamp ties by id so the order is stable", () => {
-    const sorted = sortSettledThreadsForSidebar([
-      settled({ id: "b", settledAt: "2026-03-09T10:00:00.000Z" }),
-      settled({ id: "a", settledAt: "2026-03-09T10:00:00.000Z" }),
-    ]);
-
-    expect(sorted.map((thread) => thread.id)).toEqual(["a", "b"]);
-  });
-});
-
 describe("resolveWorkingStartedAt", () => {
   const session = {
     threadId: ThreadId.make("thread-1"),
@@ -2375,6 +2307,49 @@ describe("sortProjectsForSidebar", () => {
     ]);
   });
 
+  it.each(["updated_at", "created_at"] as const)(
+    "matches the per-comparison %s order on a shuffled list with ties",
+    (sortOrder) => {
+      const minute = (value: number) => `2026-03-09T10:0${value}:00.000Z`;
+      // (index * 7) % 24 scrambles the input order. Titles repeat, and
+      // projects 16-23 have no threads, so they use their own stamps.
+      const projects = Array.from({ length: 24 }, (_, index) => {
+        const n = (index * 7) % 24;
+        return makeProject({
+          id: ProjectId.make(`project-${n}`),
+          title: n % 2 === 0 ? "Alpha" : "Beta",
+          createdAt: minute(n % 3),
+          updatedAt: n % 5 === 0 ? "invalid" : minute(n % 2),
+        });
+      });
+      const threads = Array.from({ length: 48 }, (_, n) => ({
+        projectId: ProjectId.make(`project-${n % 16}`),
+        createdAt: minute(n % 6),
+        updatedAt: minute(n % 3),
+        latestUserMessageAt: n % 4 === 0 ? null : minute(n % 5),
+      }));
+      // The comparator this sort replaced: it walked each project's threads
+      // on every call.
+      const timestamp = (project: Project) =>
+        getProjectSortTimestamp(
+          project,
+          threads.filter((thread) => thread.projectId === project.id),
+          sortOrder,
+        );
+      const expected = projects.toSorted((left, right) => {
+        const rightTimestamp = timestamp(right);
+        const leftTimestamp = timestamp(left);
+        const byTimestamp =
+          rightTimestamp === leftTimestamp ? 0 : rightTimestamp > leftTimestamp ? 1 : -1;
+        return (
+          byTimestamp || left.title.localeCompare(right.title) || left.id.localeCompare(right.id)
+        );
+      });
+
+      expect(sortProjectsForSidebar(projects, threads, sortOrder)).toEqual(expected);
+    },
+  );
+
   it("returns the project timestamp when no threads are present", () => {
     const timestamp = getProjectSortTimestamp(
       makeProject({ updatedAt: "2026-03-09T10:10:00.000Z" }),

apps/web/src/components/Sidebar.logic.ts

@@ -16,10 +16,8 @@ import {
 } from "@t3tools/client-runtime/state/thread-settled";
 import {
   getThreadSortTimestamp,
-  resolveSettledThreadTimestamp,
   sortThreads,
   toSortableTimestamp,
-  type SettledThreadTimestampInput,
   type ThreadSortInput,
 } from "../lib/threadSort";
 import type { SidebarThreadSummary, Thread } from "../types";
@@ -937,20 +935,6 @@ export function reduceSidebarProjectScopeMenuState(
   }
 }
 
-// Settled rows are history, so they order by when the work ENDED, not when
-// the thread was created or last touched.
-export function sortSettledThreadsForSidebar<
-  T extends SettledThreadTimestampInput & { readonly id: string },
->(threads: readonly T[]): T[] {
-  const timestampMs = (thread: T) => {
-    const timestamp = resolveSettledThreadTimestamp(thread);
-    return timestamp === null ? 0 : Date.parse(timestamp);
-  };
-  return [...threads].toSorted(
-    (left, right) => timestampMs(right) - timestampMs(left) || left.id.localeCompare(right.id),
-  );
-}
-
 /** The timestamp a working thread's elapsed label counts from: the running
     turn's start (request time until adoption), falling back to the session's
     last transition when the turn projection lags behind. Malformed
@@ -1136,13 +1120,19 @@ function sortProjectsByActivity<TProject extends SidebarProject>(
     return [...projects];
   }
 
-  return [...projects].toSorted((left, right) => {
-    const rightTimestamp = getProjectSortTimestamp(right, getProjectThreads(right), sortOrder);
-    const leftTimestamp = getProjectSortTimestamp(left, getProjectThreads(left), sortOrder);
-    const byTimestamp =
-      rightTimestamp === leftTimestamp ? 0 : rightTimestamp > leftTimestamp ? 1 : -1;
-    return byTimestamp || compareTies(left, right);
-  });
+  // Each project's timestamp walks all of its threads, so compute it once
+  // per project instead of once per comparison.
+  return projects
+    .map((project) => ({
+      project,
+      timestamp: getProjectSortTimestamp(project, getProjectThreads(project), sortOrder),
+    }))
+    .sort((left, right) => {
+      const byTimestamp =
+        right.timestamp === left.timestamp ? 0 : right.timestamp > left.timestamp ? 1 : -1;
+      return byTimestamp || compareTies(left.project, right.project);
+    })
+    .map(({ project }) => project);
 }
 
 export function sortProjectsForSidebar<

apps/web/src/components/Sidebar.tsx

@@ -21,7 +21,10 @@ import {
   effectiveSnoozed,
   threadWokeAt,
 } from "@t3tools/client-runtime/state/thread-settled";
-import { resolveSettledThreadTimestamp } from "@t3tools/client-runtime/state/thread-sort";
+import {
+  resolveSettledThreadTimestamp,
+  sortSettledThreads,
+} from "@t3tools/client-runtime/state/thread-sort";
 import {
   threadSearchMatchKey,
   type EnvironmentThreadSearchMatch,
@@ -181,7 +184,6 @@ import {
   sidebarMarkerId,
   sortLogicalProjectsForSidebar,
   sortPinnedThreadsForSidebar,
-  sortSettledThreadsForSidebar,
   sortThreadsForSidebar,
   useRetainedValue,
   useSidebarRowSubscriptionLease,
@@ -2626,7 +2628,7 @@ export default function Sidebar() {
           firstValidTimestampMs(left.snoozedUntil ?? null) -
           firstValidTimestampMs(right.snoozedUntil ?? null),
       ),
-      settledThreads: sortSettledThreadsForSidebar(settled),
+      settledThreads: sortSettledThreads(settled),
       snoozeNow: preciseNow,
     };
   }, [nowMinute, optimisticDrop, scopedProjectKeys, serverConfigs, snoozeWakeTick, threads]);
@@ -3452,7 +3454,7 @@ export default function Sidebar() {
     if (dragState === null || thread === undefined) return [];
     const key = (candidate: EnvironmentThreadShell) =>
       scopedThreadKey(scopeThreadRef(candidate.environmentId, candidate.id));
-    return sortSettledThreadsForSidebar([
+    return sortSettledThreads([
       ...settledThreads.filter((candidate) => key(candidate) !== dragState.activeKey),
       applySidebarThreadDrop(thread, "settled", dragState.occurredAt),
     ]).map(key);

apps/web/src/lib/threadSort.ts

@@ -1,9 +1,7 @@
 export {
   getLatestThreadForProject,
   getThreadSortTimestamp,
-  resolveSettledThreadTimestamp,
   sortThreads,
   toSortableTimestamp,
-  type SettledThreadTimestampInput,
   type ThreadSortInput,
 } from "@t3tools/client-runtime/state/thread-sort";